When I was younger I had both a small sailboat and my "play" powerboat (Outboard).
One night it was a full moon and we were partying when this girl said she always wanted to water ski in the nude.
Well we were more than willing to make her dream come true. There were plenty of "spotters" to keep an eye on her and I had this light for her to wear in case she crashed, she turn it on to help find. But, full moon it was like day time.
When we were finished instead of tying up at the end of the dock I just beached the boat and we all went back in the house to finish off the beer.
The next morning a buddy wakes me up saying my boat was swamped. The automatic bilge pump did not come on. So, him and me went down to the boat to fix. He was holding the battery so I could reconnect the wires.
I was young, remember? I only had two hands and decided my mouth work as a third hand to hold a wire. My friend start yelling; "No, No, No"! Too late, I stuck that wire in my mouth standing in the water and my hangover was cured. I was lucky it not kill me.
That was the stupidest, bonehead thing I ever done. After that I learned to keep a few small strips of "Duck Tape" on my nose to grab when I needed to stick something to hold as my third hand.
I doubt anyone here can top that for the "Bonehead Award"